Electrical connections for modular building constructions

ABSTRACT

An electrical connector, for use between a rising cable in a column of a building structure and a line branched off that cable at a floor level, includes a gripper member with a cable-engaging bight portion and a transverse portion in which a piercing member is slidably and rotatably mounted. The piercing member has a flattened penetrating end which, after being driven into the core of the multistrand cable and turned through 90*, spreads the strands and wedges the cable sheath tightly in the bight of the gripper; the opposite end of the piercing member has an axial bore of polygonal profile in which a terminal of a branch lead is clamped by means of a resilient insert.

[ 1 Sept. 5, 1972 FOREIGN PATENTS OR APPLICATIONS 450,514 4/1968 Switzerland..............339/97 T 15,813 9/1892 Great Brita n...........339/97 R Primary Examiner-Joseph H. McGlynn Attorney-Karl F. Ross [57] ABSTRACT An electrical connector, for use between a rising cable in a column of a building structure and a line branched ofi that cable at a floor level, includes a gripper member with a cable-engaging bight portion and a transverse portion in which a piercing member is slidably and rotatably mounted. The piercing member has a flattened penetrating end which, after being driven into the core of the multistrand cable and turned through 90, spreads the strands and wedges MODULAR BUILDING CONSTRUCTIONS Myron Jenner, c/o Jen Products, Inc., Bethel, Vt. 05032 Feb. 11, 1970 [21] Appl. No.: 10,463

..339/97 R .H0lr 11/20 .339/20-22, 95, 339/97-99 References Cited UNITED STATES PATENTS United States Patent Jenner [54] ELECTRICAL CONNECTIONS FOR [72] Inventor:

[22] Filed:

[51] Int. Cl.

[58] Field of the cable sheath tightly in the bight of the gripper; the opposite end of the piercing member has an axial bore of polygonal profile in which a terminal of a branch lead is clamped by means of a resilient insert.

8 Claims, 11 Drawing Figures PATENTEDSEP 1912 3.689.867

F/G.l 22 A INVENTOR. MYRON JENNER PATENTEDSEP 9 3.689.867

sum 2 OF 3 3/ F l6.7a

VI I/1111114 NW m") PATENTED SEP 5 I973 SHEET 3 BF 3 ATTORNEY DESCRIPTION OF INVENTION The present invention relates to an electrical conduit connector particularly useful in conjunction with prefabricated building modules.

Although not limited thereto, the present invention will be particularly described in connection with this application to a prefabricated module for a prefabricated building which may have six stories and in which each of the corner supporting columns are hollow and of rectangular cross-section. The main electrical cable extends through each of the modules and the present invention is particularly directed to the means by which connections may be made to the cable at each floor or at each stage of the modular assembly.

It is among the objects of the present invention to provide a simple durable electrical connector for modular buildings which will permit electrical connections to be properly made in accordance with safety regulations at each floor.

Another object of my invention is to provide an electrical connector system, particularly designed for prefabricated modular building units, in which electrical junctions may be readily made to a common cable extending from the base to the uppermost floor of each module with reduction of the risk of short circuits, disconnection or violations of various underwriters codes.

A further object is to provide a simple and durable, readily installed and maintained electrical connector system for modular building structures in which the number of parts and complexity of the connection are reduced to a minimum and in which the connection may be readily made without interference with any other facilities included in the building construction.

Still further objects and advantages will appear in the more detailed description set forth below, it being understood, however, that this more detailed description is given by way of illustration and explanation only and not by way of limitation, since various changes therein may be made by those skilled in the art without departing from the scope and spirit of the present invention.

In accomplishing the above objects I may provide a modular building construction with four spaced rectangular-cross-section hollow metal columns, one at each corner of the module, which are firmly mounted by a suitable socket or shoe in the base or ground and which may extend say six stories in height.

At each story or level the module is provided with a floor consisting of supporting hollow rectangular crossbeams, disposed on each side of the module and firmly attached to the sides of the vertical columns of the modules.

These modules are pre-assembled to have exterior walls, interior fittings to the ceilings and floors and also the necessary utilities. The present invention is particularly directed to the construction of the electrical connections, which may be established by extending an insulated cable through the hollow columns, past the various stories or floors.

These modules are generally prefabricated at a site away from the building site and are transported to the building site by special trucks and then erected by special gantries in side-by-side relationship. The corners of the buildings are formed by single modules each having a single exterior column, while the exterior sides of the building are formed by double columns at each module junction. Interiorly, the four adjacent modular columns come together and are suitably joined and clamped or otherwise interconnected in the final building structure.

For each floor of each module, one of the columns 0 carries the main electrical cable constituting a source of l 10 or 220 AC or DC current. Adjacent the floor of each level in the module there is provided an opening into the interior of the modular column covered by a closure plate which may be opened to permit access to one or more of the cables within the column.

These cables desirably each have a heavy insulating sheath enveloping a twisted group of conduit wires or strands. Two, three, or four of these cables may be provided for serving different purposes, such as different voltage or current supplies. The exterior of the column also may carry a standard electrical junction box.

The present invention will be particularly described with reference to the electrical connection provided between the interior cable and the exterior electrical facilities. The basic element of the connection is a hook member which has a curved U-shaped portion or bight snugly engaging the cable and spacedly confronting a transverse leg of an L-shaped extension of one of the legs of the U bearing a penetrating member adapted to pierce the sheath and to make contact with the separate wires in the electrically conducting cable core.

This hook member and its L-shaped extension are sheathed in insulating material, such as a phenol formaldehyde plastic. The penetrating implement comprises a cylindrical base circular portion which may terminate in a piercing point having side ridges which penetrate through the cable sheath and also engage and separate the cable strands.

This penetrating member may be forced into the cable by means of a tool, which can be hydraulically or pneumatically driven and which may have detachable claws to engage the base or L-shaped portion of the penetrating member. The penetrating member also has a central axial opening permitting the insertion of the tip of the pneumatic or hydraulic tool to press the penetrating member into the vertical cable.

After insertion of the fluid-operated tool a handle may be provided on its outwardly extending end of the piston to enable turning of this tool through so that the wires will be separated by the notches or grooves in the penetrating member. The axial opening is desirably polygonal or off-round in cross-section and the tip of the pneumatic or hydraulic tool may be matchingly shaped. A spring-pressed stop or latch member may also be provided in the L-shaped extension of the connector to arrest the penetrating member in its final position turned through 90.

After the hydraulically or pneumatically driven pusher has been removed, a resilient clamping member may be inserted into the axial bore of noncircular cross-section as a terminal for the branch lead to be connected to the rising cable. This clamping member may consist of two halves defining a central circular recess which will closely accommodate the electrical branch conductor.

This branch conductor may extend into a standard electrical junction box hinged to the face. of the vertical column at the edge of the access opening. There may be an uninsulated separate ground wire extending parallel to the cable within the vertical column, if necessary. Two of these electrical connections may be provided for each floor on opposite contacting modular columns, or the electrical connections may be made all to one modular column for an entire group of four modules.

Each floor may use the same connection, or a single column may be provided with three cable members, serving alternately for successive floors.

In the drawing wherein like reference characters denote corresponding parts throughout the several views:

FIG. 1 is a side fragmentary elevational view partly in section showing part of a modular column with a floor associated therewith and a closed opening giving access to an interior cable;

FIG. 2 is a transverse sectional horizontal view taken on the line 22 of FIG. 1;

FIG. 3 is a fragmentary side elevational vertical view of a connector according to my invention fitting into the access opening of FIGS. 1 and 2;

FIG. 4 is a transverse horizontal sectional view taken on the line 4-4 of FIG. 3;

FIG. 5 is a transverse vertical sectional view showing the insertion of the penetrating member of the connector into the cable, together with a driving tool therefor;

FIG. 6 is a fragmentary transverse horizontal sectional view of the connector, drawn to a larger scale and showing the penetrating implement in piercing position;

FIG. 7 is a transverse fragmentary horizontal sectional view, onthe same scale as FIG. 6, showing the implement turned through 90 after having been in serted into the sheath and wires of the cable;

FIG. 7a is a vertical transverse sectional view, drawn to an enlarged scale as compared to FIG. 7 and at right angles to the view of FIG. 6, showing the head of the penetrating implement in position within the separately wound strands of cable core;

FIG. 8 is a perspective side view of a metal clip or socket fitting in the central axial opening bore of the shank of the penetrating implement;

FIG. 9 is a transverse vertical sectional horizontal view, drawn to a larger scale, of the clip of FIG. 8 lodged in the bore of the penetrating implement; and

FIG. 10 is a transverse vertical sectional view taken on the line 10-10 of FIG. 7 and drawn to the enlarged scale of FIG. 9.

In FIGS. 1 and 2 there is shown a corner column A of a building structure having a side opening B which may be closed by a door C providing with a spring hinge D. with these openings B there may be associated an electrical junction box, not shown, in which case the closure door C may be omitted; this junction box may be either provided with a hinge D or directly fitted on the opening B. It is noted that the column A is four-sided and is located at one corner of the module; its walls may be extruded but can also be formed of sheet steel or other metal folded and butt-welded at an interior or side face. The columns A carry transverse beams E which are also hollow and may be welded or otherwise ferent machines or special circuits for radio and television or for other purposes. The cables may be part of a three-phase system, whether delta or Y connected.

In FIGS. 3 and 4 I have shown a gripping member G which consists at one end of a hook to snugly embrace the cable F and at the other end of a an L-structure to carry a penetrating member or piercing implement H. The implement H has a ridged spike portion J to penetrate and contact the interior strands of the cable F; a latch K in member G serves to hold the penetrating element H in a predetermined rotary position.

To enable penetration of the ridged or grooved point J into the cable F, I provide a pressure tool or driver L having a pneumatic or hydraulic cylinder and claws N to engage the outer portion of the gripper G.

The outer end 73a of the tool L, as shown in FIG. 5, is provided with a handle to permit turning of the penetrating implement J through from its insertion position (FIG. 6) into an offset position (FIG. 7a) in which it is locked by the snap-in device K shown retracted in FIG. 4 and engaged in FIG. 7.

In the position of FIGS. 7 and 7a, the flattened end J of implement H has been forced into the cable F to spread its strands against the insulating cable sheaths.

Within the lower shank of the implement I-I may be inserted a clip Q. Designed to engage a terminal of a branch lead M extending into the aforementioned junction box from which current may be distributed within the apartment or other enclosure on the respective story or floor of the assembled building.

The column A shown in FIGS. 1 and 2 has a vertical rectangular cross-section a hollow interior 20, through which extend the electrical conduits generally designated F, three such conduits being shown at 21, 22 and 23; they may form part of a three-phase system or convey different frequencies or different voltages.

Along the exterior sides between the corners, the modules A are paired, leaving only two interior walls for openings such as B. Within the interior of the building structure, four modular columns A are grouped together, and here again only two interior walls of the modular column A are available for openings B.

As shown in FIG. 1, the cross-section of the transverse or cross-beams E has a depth which is greater than the width of the vertical columns A; the beam width, however, is less than that of the vertical columns A so that there may be spaces on one or both sides.

Although the cross-members E are of rectangular hollow cross-section, they may also take other shapes. Each cross-member is welded, as indicated at 25, to one wall 26 of the column A and carries a flooring 27, together with suitable floor covering such as tile or carpeting 28 and 29.

The cable 30 shown in FIGS. 3 and 4 has an outer sheath 30, of insulating plastic rubber or the like, which surrounds the conductive core of twisted strands 31.

The hook member gripper G has a central metal core 32 of semicircular shape with a straight extension 33 and a transverse member 34. This member should be made from a fairly strong metal, such as steel, and carries an insulating coating of resin, plastic, rubber or the like, indicated at 35.

The semi-circular inside face 36 of the bight portion of member G is designed as a cradle for the insulating sheath 30 of the cable F which, upon the aforedescribed spreading of the strands by the penetrator J, will be tightly pressed against the interior faces 37 and 38 of the legs of the U-shaped part 32, thereof.

The base 39 of the member G may be rectangular or square, as shown in FIG. 3.

The sharp-edged spike J has a penetrating point 41 and is flat in cross-section; recesses 42 on its corrugated sides, receiving individual cable strands in the offset position of FIG. 7, are separated by ridges 43. The penetrating member H is closely fitted in an opening of transverse leg 34 44 by its enlarged shank which has sloping shoulders 45 joining it to the ridged spike portion J. This shank has a cylindrical portion 46 which is held in position by its close fit in the opening 44 as well as in aligned openings 47 and 48 formed in the plastic coating 35 of the gripper G.

The upper portion of the cylindrical base 46 of the implement H has a transverse bore 49 which communicates midway with an axial bore 50 of hexagonal cross-section having about the same diameter. The latch member K has a cylindrical portion 51 riding in a transverse bore 52 of leg 34 under the pressure of a coil spring 53 tending to drive it into a lateral recess 54 of the cylindrical shank 46 upon rotation of the implement into the position of FIGS. 7 and 7a,

The inner end of the member 51 has a conical tip 55 confronting the shank 46.

The tool of FIG. 5 L has a square base 65 to which arms 67 of claws R are pivotally attached at 66. Arms 67 terminate in transverse lugs 68, latching onto the side edges 69 of the transverse portion 34 of member G.

Attached to the base 65 is the cylinder 70, which is closed at 71 and receives to piston member 72. This piston member has a reduced piston rod 73 which extends outwardly through an opening 74 in the cylinder bottom 71. The other side of the piston carries a connecting rod 75, which extends through an opening 76 in the block 65.

This large diameter rod 75 has a reduced extremity 77, of hexagonal cross-section, which fits into the axial bore 50 of the penetrating member H. When the leg 34 is engaged at the edges 69, the piston 72 can be actuated by pneumatic or hydraulic pressure to force the corrugated spike J into the sheath 30 of the cable F and then into the core 31, as illustrated in FIG. 6.

When the turning of the spike J into the positions of FIGS. 7 and 7a establishes firm conductive contact with the cable strands 31, sheath 30 is expanded into close contact, as indicated at 89, with the interior face 90 of the bight of the gripper G. A shoulder 91 of the implement H serves as a stop and also bears upon the elastic sheath 30 to intensify the contact pressure. After the detent 51 has snapped into the recess 54 in the lower portion of the implement H, the extremity 77 of diver L may be withdrawn. FIG. 7a shows the cable sheath 30 deformed at 92 against the inside face 93 of the insulating lines of the member 32.

The helically twisted strands 31 in FIG. 7a are shown separated at 94, spread by the ridges 43 of spike J.

In FIGS. 8, 9 and 10 I have shown details of the clip Q, which may be inserted into the bore 50 to receive the conductive terminal of branch lead M. This insert comprises two symmetrical side members 10; of undulating shape having a central arcuate elongated portion 101 with outwardly extending wings 102 which contact the wall surface of the axial bore 50, as shown at 103 and 104.

FIG. 9 shows-a cross-section of the spring chip 0 defining a socket 105 for the terminal portion 106a (FIG. 10) of the branching cable M shown in FIG. 7.

It will be noted that the wings 102 of the conductive insert Q bear upon opposite faces of the axial bore 50, in their idle state whereas when they are expanded by insertion of a conductor 106a they extend into respective corners of the hexagonal profile. The free ends of these wings are flared outwardly, as indicated at a in FIG. 8, to permit easier insertion of the member 106a.

The elastic insert Q has an end plate 106 whose curled sides form springs 107, which hold it in position in the transverse passage 49 of FIG. 7 by coming to rest on the lower surface 108 thereof. The end plate 106 interconnects the upper ends of the arcuate side portions 101 and the wings 102.

Thus, I have provided a simple, readily installed electrical connector for joining branch circuits to a vertically extending cable, this connector being durable, not liable to any short circuits, and substantially tamperproof.

Having now particularly described and ascertained the nature of the invention, and in what manner the same is to be performed, what is claimed is:

1. A connector -for conductively joining a branch lead to a stranded cable provided with an insulating sheath, comprising a gripper member having a bight portion engageable with the cable, a transverse portion spacedly confronting said gripper portion and integral therewith, and an axially slidable piercing implement lodged in said transverse portion in line with the apex of said bight portion, said implement having a flattened pointed end facing said bight portion and an opposite recessed end for receiving the branch lead, said implement being rotatable in said transverse portion between an insertion position with said flattened end lying in the axial plane of the cable and an offset position substantially at right angles thereto with said flattened end spreading the cable strands, said recessed end being provided with an axial formation of noncircular crosssection engageable by a tool for axially advancing and rotating said implement.

2. A connector as defined in claim 1, further comprising laterally movable latch means in said gripper member engageable with said implement for retaining same in said offset position.

3. A connector as defined in claim 1 wherein said pointed end is the tip of a spike having a corrugated lateral surface with axially spaced grooves accommodating individual cable strands.

4. A connector as defined in claim 1 wherein said formation is a bore, further comprising symmetrical shell portions of elastic material having each pair of removably fitted in said bore for clamping engagement with a terminal of said branch lead.

5. A connector as defined in claim 4 wherein said cross-section is polygonal, said insert including two pair of lateral wings fitted into respective corners of the polygon.

6. A connector as defined in claim 1 wherein said gripper member has a U-shaped end forming said bight portion, said transverse portion being part of an L- shaped extension of one of the legs of the U.

7. A connector as defined in claim 6 wherein the gripper member is formed with an open side opposite said one of said legs for enabling the introduction of the cable into said bight portion.

8. A connector for conductively joining a branch lead to a stranded cable provided with aninsulating sheath, comprising a gripper member having a bight portion engageable with the cable, a transverse portion spacedly confronting said gripper portion and integral therewith, and an axially slidable piercing implement lodged in said transverse portion in line with the apex of said bight portion, said implement having a pointed end constituted by a flattened tip of a spike facing said bight portion and an opposite recessed end for receiving the branch lead, said implement being rotatable in said transverse portion between an insertion position with said flattened tip lying in the axial plane of the cable and an offset position substantially at right angles thereto with said flattened tip spreading the cable strands, said spike having a corrugated lateral surface with axially spaced grooves accommodating individual cable strands. 

1. A connector for conductively joining a branch lead to a stranded cable provided with an insulating sheath, comprising a gripper member having a bight portion engageable with the cable, a transverse portion spacedly confronting said gripper portion aNd integral therewith, and an axially slidable piercing implement lodged in said transverse portion in line with the apex of said bight portion, said implement having a flattened pointed end facing said bight portion and an opposite recessed end for receiving the branch lead, said implement being rotatable in said transverse portion between an insertion position with said flattened end lying in the axial plane of the cable and an offset position substantially at right angles thereto with said flattened end spreading the cable strands, said recessed end being provided with an axial formation of noncircular crosssection engageable by a tool for axially advancing and rotating said implement.
 2. A connector as defined in claim 1, further comprising laterally movable latch means in said gripper member engageable with said implement for retaining same in said offset position.
 3. A connector as defined in claim 1 wherein said pointed end is the tip of a spike having a corrugated lateral surface with axially spaced grooves accommodating individual cable strands.
 4. A connector as defined in claim 1 wherein said formation is a bore, further comprising symmetrical shell portions of elastic material having each pair of removably fitted in said bore for clamping engagement with a terminal of said branch lead.
 5. A connector as defined in claim 4 wherein said cross-section is polygonal, said insert including two pair of lateral wings fitted into respective corners of the polygon.
 6. A connector as defined in claim 1 wherein said gripper member has a U-shaped end forming said bight portion, said transverse portion being part of an L-shaped extension of one of the legs of the ''''U.''''
 7. A connector as defined in claim 6 wherein the gripper member is formed with an open side opposite said one of said legs for enabling the introduction of the cable into said bight portion.
 8. A connector for conductively joining a branch lead to a stranded cable provided with an insulating sheath, comprising a gripper member having a bight portion engageable with the cable, a transverse portion spacedly confronting said gripper portion and integral therewith, and an axially slidable piercing implement lodged in said transverse portion in line with the apex of said bight portion, said implement having a pointed end constituted by a flattened tip of a spike facing said bight portion and an opposite recessed end for receiving the branch lead, said implement being rotatable in said transverse portion between an insertion position with said flattened tip lying in the axial plane of the cable and an offset position substantially at right angles thereto with said flattened tip spreading the cable strands, said spike having a corrugated lateral surface with axially spaced grooves accommodating individual cable strands. 